Gas standards to support calibration of natural gas analysers
NPL's natural gas standards are typically used to calibrate gas analysers. This enables the composition of real natural gases to be determined, which in turn allows accurate calculation of the calorific value and other physical properties of the gas.
In addition to the components usually found in synthetic natural gas standards (C1 to C5 alkanes, n-hexane, nitrogen and carbon dioxide), NPL's standards can also contain C6 to C10 hydrocarbon components. Accurate measurement of these components is particularly useful when the hydrocarbon dew point is to be calculated, reassuring the gas transporter that condensation of the mixture will not take place in the gas pipeline.
The range of natural gas standards covered by NPL's UKAS accreditation is shown below.
| Component |
Amount fraction
range (cmol/mol) * |
| Methane |
55.0 to 99.9 |
| Nitrogen |
0.02 to 25.2 |
| Carbon dioxide |
0.04 to 25.0 |
| Ethane |
0.008 to 18.0 |
| Propane |
0.008 to 8.0 |
| i-butane |
0.004 to 1.7 |
| n-butane |
0.004 to 1.7 |
| neo-pentane |
0.0005 to 0.50 |
| i-pentane |
0.0025 to 0.60 |
| n-pentane |
0.0025 to 0.60 |
| n-hexane |
0.0008 to 0.50 |
| Helium |
0.0014 to 0.50 |
| Oxygen |
0.05 to 1.0 |
| Component |
Amount fraction
range (µmol/mol) |
| Benzene |
5 to 500 |
| Toluene |
5 to 250 |
| Cyclohexane |
10 to 400 |
| Methylcyclohexane |
10 to 400 |
| n-heptane |
10 to 500 |
| n-octane |
5 to 200 |
| n-nonane |
1 to 120 |
| n-decane |
1 to 20 |
* 1 cmol/mol is equal to 0.01 mol/mol and is equivalent to the 'unit' % mol/mol often used by the natural gas industry
Hydrogen enriched natural gas
NPL can provide traceable gas standards to support the accurate quantification of high levels of hydrogen in natural gas. Please contact us for more information.
Other components
NPL's natural gas PRGMs may also contain other hydrocarbon isomers not listed in the above table. Examples of these components include, but are not restricted to:
- cyclopentane
- 2,2-dimethylbutane
- 2,3-dimethylbutane
- 2-methylpentane
- 3-methylpentane
- 2-methylhexane
Don’t see what you are looking for? Our diverse skill set enables us to provide bespoke solutions. Please contact us to discuss your requirements.
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